1. Field of the Invention
The present invention relates to a carbide rotary tool, and specifically relates to a carbide rotary tool that is made from cemented carbide.
2. Description of Related Art
A so-called “throw-away type” cutting tool is known for which a detachable tip that has a cutting edge portion can be mounted on an end of a rod. Significant savings can be achieved with the tool, because when the tip becomes worn, only the tip needs to be replaced, and the rod can be reused. For example, a tungsten steel cutting blade structure is known in which a threaded shaft that is provided in a bottom portion of a tool bit (a tip) is screwed into a female threaded portion that is provided in the end of a rod (refer to Patent Document 1, for example). For a tool that has this sort of structure, in a case where the tool bit is manufactured from cemented carbide, for example, the cutting edge portion and the threaded shaft are manufactured by being cut from a (solid) piece of the cemented carbide.    Patent Document 1: Japanese Registered Utility Model No. 3132125